Magnetic sensors with effectively shaped side shields

ABSTRACT

Magnetic sensors with effectively shaped side shields and their fabrication processes are provided. One such process includes depositing sensor materials on a substrate, shaping the sensor materials to form a stripe height of the magnetic sensor, shaping the sensor materials to form a track width of the magnetic sensor, depositing side shield materials on the shaped sensor materials, shaping the side shield materials such that a resulting side shield extends further than the stripe height, depositing an insulator layer on the shaped side shield materials, and shaping the insulator layer.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a divisional application and claims priority to andthe benefit of U.S. application Ser. No. 15/870,779, filed on Jan. 12,2018, having Attorney Docket No. WDT-1215 (WDA-3410-US) and entitled,“MAGNETIC SENSORS WITH EFFECTIVELY SHAPED SIDE SHIELDS”, the entirecontent of which is incorporated herein by reference.

FIELD

The present invention relates to magnetic data recording, and moreparticularly to magnetic sensors with effectively shaped side shieldsand their fabrication processes.

INTRODUCTION

Computer systems commonly include an information storage device that isreferred to as a magnetic disk drive. The magnetic disk drive includes arotating magnetic disk, write and read heads that are suspended by asuspension arm adjacent to a surface of the rotating magnetic disk andan actuator that swings the suspension arm to place the read and writeheads over selected tracks on the rotating disk. The read and writeheads are directly located on a slider that has an air bearing surface(ABS). The suspension arm biases the slider into contact with thesurface of the disk when the disk is not rotating, but when the diskrotates air is swirled by the rotating disk. When the slider rides onthe air bearing surface, the write and read heads are employed forwriting magnetic impressions to and reading magnetic impressions fromthe rotating disk. The read and write heads are connected to processingcircuitry that operates according to a computer program to implement thereading and writing functions.

The write head generally includes at least one coil, a write pole andone or more return poles. When current flows through the coil, aresulting magnetic field causes a magnetic flux to flow through thewrite pole, which results in a magnetic write field emitting from thetip of the write pole. This magnetic field is sufficiently strong thatit locally magnetizes a portion of the adjacent magnetic media, therebyrecording a bit of data. The write field then travels through amagnetically soft under-layer of the magnetic medium to return to thereturn pole of the write head.

Magnetoresistive sensors such as a Giant Magnetoresistive (GMR) sensors,Tunnel Junction Magnetoresistive (TMR) sensors or a scissor typemagnetoresistive sensors have been employed in read heads to read amagnetic signal from the magnetic media. Such a magnetoresistive sensorhas an electrical resistance that changes in response to an externalmagnetic field. This change in electrical resistance can be detected byprocessing circuitry in order to read magnetic data from the magneticmedia.

The build processes for fabricating a read head typically involves oneof two possible build schemes. One such scheme, which may be referred toas K3 first, involves patterning a stripe height of the sensor firstbefore forming other read head components. The second such build scheme,which may be referred to as K5 first, involves patterning a track widthof the sensor first before forming other read head components. However,these build schemes have a number of disadvantages that do not allow forthe formation/shaping of effective side shields, particularly in thecase of smaller geometries associated with modern read heads configuredfor high density magnetic recording.

SUMMARY

In one aspect, the disclosure relates to a magnetic sensor including asubstrate, a sensor stack disposed on the substrate and having a stripeheight, where the sensor stack further includes a front edge disposed atan air bearing surface (ABS) of the magnetic sensor, a back edgeopposite of the front edge, and two side edges, and a side shieldadjacent to each of the two side edges of the sensor stack, each sideshield having a side shield height defined as a distance from the ABS toa back edge of the side shields, where the side shield height is greaterthan the stripe height, and where substantially no residue frommaterials used to form the side shield are disposed at the back edge ofthe sensor stack.

In another aspect, the disclosure relates to a method of fabricating amagnetic sensor having an air bearing surface (ABS), includingdepositing sensor materials on a substrate, shaping the sensor materialsto form a stripe height of the magnetic sensor, shaping the sensormaterials to form a track width of the magnetic sensor, depositing sideshield materials on the shaped sensor materials, shaping the side shieldmaterials such that a resulting side shield extends further than thestripe height, depositing an insulator layer on the shaped side shieldmaterials, and shaping the insulator layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top schematic view of a disk drive configured for heatassisted magnetic recording (HAMR) including a magnetic sensor witheffectively shaped side shields in accordance with one embodiment of thedisclosure.

FIG. 2 is a side schematic view of the slider and HAMR magnetic mediumof FIG. 1 where the slider includes the magnetic sensor/reader witheffectively shaped side shields in accordance with one embodiment of thedisclosure.

FIG. 3 is top schematic view of a magnetic sensor with effectivelyshaped side shields in accordance with one embodiment of the disclosure.

FIG. 4 is a flowchart of a process for fabricating a magnetic sensorwith effectively shaped side shields in accordance with one embodimentof the disclosure.

FIGS. 5a to 5k illustrate a process for fabricating a magnetic sensorwith effectively shaped side shields in accordance with one embodimentof the disclosure.

FIG. 6 is a flowchart of a second process for fabricating a magneticsensor with effectively shaped side shields in accordance with oneembodiment of the disclosure.

FIG. 7 is a top schematic view of various masking layers that may beused in a process for fabricating a magnetic sensor with effectivelyshaped side shields in accordance with one embodiment of the disclosure.

FIG. 8 is a top schematic view of various masking layers on a magneticsensor workpiece that illustrate various constraints that may be used ina process for fabricating a magnetic sensor with effectively shaped sideshields in accordance with one embodiment of the disclosure.

DETAILED DESCRIPTION

As described above, reader designs in general consist of two types ofbuild schemes (K5 first, K3 first), whereby either the stripe height isformed first (K3 first) or after the track-width (K5 first). Each schemehas advantages and disadvantages. For instance, the K5 first buildscheme offers advantages such as side shield shaping and narrowtrack-width but has major disadvantages such as side shield residuals,poor refill uniformity, and free layer tails that can affect performanceand reliability. On the other hand, the K3 first build scheme offersadvantages such as pinned layer shaping and uniform refill, but hasdisadvantages such as side shields that extend to the pinned layer, noside shield shaping, and lack of narrow track-width for the sensor.These disadvantages can negatively affect self-servo writing and otherperformance (e.g., resolution, tracks per inch).

As the need to achieve increased areal density has become more importantfor magnetic storage, the inventors sought methods to harvest theadvantages of both the K3 first and K5 first build schemes. In thisdisclosure, a novel read head (e.g., magnetic sensor) with effectivelyshaped side shields and a method of fabricating the read head/sensor areproposed that incorporate the advantages of both the K5 first and K3first build schemes. In one aspect, the methods disclosed herein caninvolve shaping the side shields after shaping the stripe height of thesensor. In related art approaches, such as the K5 first build scheme,the side shields may be shaped at the same time as the stripe height, ornot shaped at all as in the case of the K3 build scheme. As a result ofthe fabrication method disclosed herein, the resulting magnetic sensorscan have a side shield height that is greater than the stripe height. Inaddition, the resulting magnetic sensors can have substantially noresidue at the back edge of the sensor stack from the materials used toform the side shield. These features provide improved sensorperformance.

The terms “above,” “below,” and “between” as used herein refer to arelative position of one layer with respect to other layers. As such,one layer deposited or disposed above or below another layer may bedirectly in contact with the other layer or may have one or moreintervening layers. Moreover, one layer deposited or disposed betweenlayers may be directly in contact with the layers or may have one ormore intervening layers.

FIG. 1 is a top schematic view of a disk drive 100 configured for heatassisted magnetic recording (HAMR) including a magnetic sensor witheffectively shaped side shields in accordance with one embodiment of thedisclosure. The laser (not visible in FIG. 1 but see 114 in FIG. 2) ispositioned with a head/slider 108. Disk drive 100 may include one ormore disks/media 102 to store data. Disk/media 102 resides on a spindleassembly 104 that is mounted to drive housing 106. Data may be storedalong tracks in the magnetic recording layer of disk 102. The readingand writing of data is accomplished with the head 108 that may have bothread and write elements. The write element is used to alter theproperties of the magnetic recording layer of disk 102 and thereby writeinformation thereto. In one embodiment, head 108 may havemagneto-resistive (MR), or giant magneto-resistive (GMR) elements. In analternative embodiment, head 108 may be another type of head, forexample, an inductive read/write head or a Hall effect head.

In operation, a spindle motor (not shown) rotates the spindle assembly104, and thereby rotates disk 102 to position head 108 at a particularlocation along a desired disk track 107. The position of head 108relative to disk 102 may be controlled by position control circuitry110.

FIG. 2 is a side schematic view of the slider and HAMR magnetic mediumof FIG. 1 where the slider includes the magnetic sensor/reader witheffectively shaped side shields in accordance with one embodiment of thedisclosure. The HAMR system components also include a sub-mount 112attached to a top surface of the slider 108. The laser 114 is attachedto the sub-mount 112, and possibly to the slider 108. The slider 108includes the write element (e.g., writer) 108 a and the read element(e.g., reader or magnetic sensor) 108 b positioned along an air bearingsurface (ABS) 108 c of the slider for writing information to, andreading information from, respectively, the media 102.

In operation, the laser 114 is configured to generate and direct lightenergy to a waveguide (possibly along the dashed line) in the sliderwhich directs the light to a near field transducer (NFT) near the airbearing surface (e.g., bottom surface) 108 c of the slider 108. Uponreceiving the light from the laser 114 via the waveguide, the NFTgenerates localized heat energy that heats a portion of the media 102near the write element 108 a. FIGS. 1 and 2 illustrate a specificembodiment of a HAMR system. In other embodiments, the magnetic sensorswith effectively shaped side shields and the corresponding fabricationprocesses disclosed herein can be used with other HAMR storage systemsor with non-HAMR storage systems.

FIG. 3 is top schematic view of a magnetic sensor 200 with effectivelyshaped side shields 204 in accordance with one embodiment of thedisclosure. The magnetic sensor 200 further includes a sensor stack 202,insulation layers 206, and a pinned layer (e.g., anti-parallel pinnedlayer extension) 208. The sensor stack 202 has a width that defines atrack width of the magnetic sensor 200, and a length/height to the ABSthat defines a stripe height (SH) of the magnetic sensor 200. As isillustrated in FIG. 3, a height of the side shield 204 to the ABS isslightly greater than the stripe height. As also illustrated in FIG. 3,no side shield residuals exist directly behind the back edge (e.g., edgeopposite the ABS edge) of the sensor stack 202. These desirable featuresenhance sensor performance and are formed during the fabricationprocessed that are described below.

In a K3 first read head, and in contrast to the improved magnetic sensor200 of FIG. 3, the side shields may extend as far as the pinned layerextension 208. In a K5 first read head, and in contrast to the improvedmagnetic sensor 200 of FIG. 3, the side shields may extend only as faras the height of the sensor stack 202. The other limitations of the K3first and K5 first build schemes are described above.

FIG. 4 is a flowchart of a process 300 for fabricating a magnetic sensorwith effectively shaped side shields in accordance with one embodimentof the disclosure. In one aspect, process 300 may be used to fabricatethe magnetic sensor 200 of FIG. 3, or any of the other magnetic sensorswith effectively shaped side shields disclosed herein. In block 302, theprocess deposits sensor materials on a substrate. In one aspect, thesensor materials include materials for a sensor stack. In one aspect,the sensor stack may include a pinned layer, a barrier layer, a freelayer, capping layer and/or other layers commonly included in a tunnelmagnetoresistance (TMR) reader stack. In one aspect, the sensor stackmay have a stacked structure that includes a pinned layer on a lowershield, a barrier layer on the pinned layer, a free layer on the barrierlayer, and a capping layer on the free layer. In other aspects, otherreader structures including the same or similar layers, and/oradditional layers, or even fewer layers, may be used for the sensorstack materials.

In block 304, the process shapes the sensor materials to form a stripeheight of the magnetic sensor. In one aspect, the shaping may includedepositing and/or patterning a photoresist layer and a first maskinglayer (e.g., diamond like carbon or DLC masking layer), etching (e.g.,reactive ion etching) the sensor materials and/or first DLC maskinglayer, milling the sensor materials, depositing an insulator layer,depositing/refilling DLC masking materials (e.g., depositing a secondDLC mask), and planarizing the workpiece (e.g., using chemicalmechanical polishing or CMP). The shaping sub-processes/actions aredescribed in more detail below.

In block 306, the process shapes the sensor materials to form a trackwidth of the magnetic sensor. In one aspect, the shaping may includedepositing and/or patterning a third DLC mask on the sensor stack and asecond insulator layer, milling the sensor materials, and/or depositinga fourth mask (e.g., SiN). The shaping sub-processes/actions aredescribed in more detail below.

In block 308, the process deposits side shield materials on the shapedsensor materials. In one aspect, the process deposits the side shieldmaterials after depositing and patterning (e.g., etching using reactiveion etching or other suitable etching technique) a second photoresistlayer. In one aspect, the process further deposits a fourth DLC masklayer on the side shield materials. In one aspect, the secondphotoresist layer and/or fourth DLC mask defines a resulting height theside shield will have. The sub-processes/actions of block 308 aredescribed in more detail below.

In block 310, the process shapes the side shield materials such that aresulting side shield extends further than the stripe height. In oneaspect, the shaping may include removing the second resist layer andselected portions of the fourth DLC mask (e.g., those portions on thesecond resist layer). In one aspect, the depositing and shaping the sideshield materials is performed after the process shapes the sensormaterials to form the track width. The sub-processes/actions of thisparagraph are described in more detail below.

In block 312, the process deposits an insulator layer on the shaped sideshield materials. In one aspect, the process deposits the insulatorlayer after depositing and patterning (e.g., etching using reactive ionetching or other suitable etching technique) a third photoresist layer,which may be referred to as a L7 layer/mask. The sub-processes/actionsof this paragraph are described in more detail below.

In block 314, the process shapes the insulator layer. In one aspect, theshaping may include removing the third photoresist layer (L7 mask) andplanarizing the workpiece. In one aspect, the process may furtherinclude further planarizing the workpiece, depositing a fourth resist,and milling portions of the side shield layer, the insulator layer,and/or a pinned layer of the sensor stack. The sub-processes/actions ofthis paragraph are described in more detail below.

In one aspect, and in addition the layers described above, other layerscommonly included in a sensor stack configured for magnetic recordingmay also be deposited and shaped during the process.

In one embodiment, the process can perform the sequence of actions in adifferent order. In another embodiment, the process can skip one or moreof the actions. In other embodiments, one or more of the actions areperformed simultaneously. In some embodiments, additional actions can beperformed.

FIGS. 5a to 5k illustrate a process 400 for fabricating a magneticsensor with effectively shaped side shields in accordance with oneembodiment of the disclosure. These figures illustrate a flowchart ofprocess actions on the left side and the corresponding structures of themagnetic sensor (e.g., workpiece) on the right side. In one aspect,process 400 may be used to fabricate the magnetic sensor 200 of FIG. 3,or any of the magnetic sensors with effectively shaped side shieldsdisclosed herein.

FIG. 5a illustrates block 402 of process 400 and a side view of theworkpiece. In block 402, the process deposits sensor materials (e.g.,materials for the sensor stack) 452 on a substrate (e.g., a magneticbottom shield or S1) 450, deposits a first DLC mask 454 and first photoresist 456 on the sensor materials 452, mills the sensor stack 452 inthe area beyond the first resist 456 and first DLC mask 454 to a freelayer 452 a of the sensor stack 452. In one aspect, the milling actiondefines a stripe height of the sensor stack 452, and the entire magneticsensor. This milling also defines a back edge of sensor stack 452. Inone aspect, the process also patterns the first DLC mask 454 and firstphoto resist 456 just after they have been deposited.

In one aspect, the sensor stack may include a pinned layer, a barrierlayer, the free layer 452 a, capping layer and/or other layers commonlyincluded in a tunnel magnetoresistance (TMR) reader stack. In oneaspect, the sensor stack may include a pinned layer on a lower shield450, a barrier layer on the pinned layer, a free layer 452 a on thebarrier layer, and a capping layer on the free layer 452 a. In otheraspects, other reader structures including the same or similar layers,and/or additional layers, may be used for the sensor stack materials. Inone aspect, the pinned layer may be made of CoFe, CoFeB, and/or othersuitable materials. In one aspect, the barrier layer may be made of MgOor other suitable materials. In one aspect, the free layer may be madeof NiFe, CoFeB, and/or other suitable materials. In one aspect, the freelayer may be made of a bi-layer including a first layer of NiFe and asecond layer of CoFeB. In one aspect, the DLC mask 454 can have athickness of about 10 nanometers (nm).

In FIG. 5a , the magnetic sensor or workpiece is shown with a side viewsuch that an air bearing surface (ABS) of the sensor is along the leftedge of the workpiece.

FIG. 5b illustrates block 404 of process 400 and a side view of theworkpiece. In block 404, the process deposits a first insulator layer458 on the sensor stack 452 and a second DLC mask 454-2 on the firstinsulator layer 458 and resist 456.

FIG. 5c illustrates block 406 of process 400 and a side view of theworkpiece. In block 406, the process removes the first resist 456 andplanarizes the workpiece (e.g., using chemical mechanical polishing).

FIG. 5d illustrates block 408 of process 400 and a side view of theworkpiece. In block 408, the process further planarizes the workpiecesuch that the first DLC mask 454 and second DLC mask 454-2 arecompletely or substantially removed.

FIG. 5e illustrates block 410 of process 400 and top and ABS views ofthe workpiece. In block 410, the process deposits a third DLC mask 460on both the sensor stack 452 and the first insulator 458, and patternsthe third DLC mask 460. In one aspect, the middle or dumbbell portion ofthe third DLC mask 460 may be used to define a track width of the sensorstack 452.

FIG. 5f illustrates block 412 of process 400 and top and ABS views ofthe workpiece. In block 412, the process mills the sensor stack 452 (inthe areas not protected by the third DLC mask 460 and first insulator458) and deposits a fourth mask 462.

FIG. 5g illustrates block 414 of process 400 and top and ABS views ofthe workpiece. In block 414, the process deposits and patterns a secondphoto resist 464, and deposits side shield materials 466 and a fifth DLCmask 468. In one aspect, the second photo resist 464 is used to define ashape of the side shield materials (e.g., side shields) 466. In oneaspect, the fifth DLC mask 468 can be used to protect against certainfuture planarization actions (e.g., to protect side shield materials 466against future CMP).

In one aspect, the soft bias layers (e.g., the resulting layers formedfrom the side shield materials) can be constructed of a single layer,bi-layer, or multilayer of soft magnetic material such as NiFe19, NiFe4,NiFe19/NiFe4, NiFe4/NiFe19, NiFe17Mo5, NiFe55, NiFe19/NiFeMo,NiFeMo/NiFe19, CoFe25, or their alloys or a combination thereof, therebyallowing the bias layers (e.g., side shield layers 466) to function asside magnetic shields as well as provide a magnetic biasing function forbiasing the free layer 452 a. In one aspect, the side shield materials466 can be made of hard bias materials such as CoPt, CoPtCr, and/orother suitable materials.

FIG. 5h illustrates block 416 of process 400 and top and ABS views ofthe workpiece. In block 416, the process removes the second photo resist464 and any layers above said resist (e.g., those portions of the sideshield materials 466 and fifth DLC mask 468 on the second resist 464).

FIG. 5i illustrates block 418 of process 400 and top and ABS views ofthe workpiece. In block 418, the process deposits and patterns a thirdphoto resist 470, and deposits insulator materials 472 (e.g., a secondinsulator layer 472). In one aspect, the third photo resist 470 (visiblein the top view but not in the ABS view as resist 470 is open there) canbe used to define a shape of the insulator materials (e.g., resulting ininsulator layer 206 in FIG. 2) 472.

In one aspect, the insulator materials 472 may be made of TaOx, Al2O3,MgO, SiOx, SiNx, SiOxNy, and/or other suitable materials, where x and yare positive integers.

FIG. 5j illustrates block 420 of process 400 and top and ABS views ofthe workpiece. In block 420, the process removes the third resist 470and planarizes the workpiece. In one aspect, the insulator materials 472have been removed from the workpiece at the ABS but remain in areasbehind the ABS. In one aspect, this removal may be performed usingresist liftoff, CMP, reactive ion etching and/or other suitable materialremoval processes.

FIG. 5k illustrates block 422 of process 400 and top and ABS views ofthe workpiece. In block 422, the process further planarizes theworkpiece (e.g., thereby removing all or substantially all of the thirdDLC mask 460), deposits a fourth photo resist 474, and mills the sideshield 466 and insulator 472. In one aspect, this milling furtherdefines the shape of the side shields and the insulator 472, and shapesa pinned layer of the sensor stack. This shaping may include shaping theextension of the anti-parallel pinned layer, such as the anti-parallelpinned layer extension 208 of FIG. 2.

In one aspect, and in addition the layers described above and depictedin FIGS. 5a to 5k , other layers commonly included in a sensor stack mayalso be deposited and shaped during the process.

As a result of this process 400, the resulting magnetic sensors can havea side shield height (e.g., preselected side shield height) that isgreater than the stripe height. In addition, the resulting magneticsensors can have substantially no residue at the back edge of the sensorstack from the materials used to form the side shield. These featuresprovide improved sensor performance.

In several embodiments, the deposition of such layers can be performedusing a variety of deposition sub-processes, including, but not limitedto physical vapor deposition (PVD), sputter deposition and ion beamdeposition, and chemical vapor deposition (CVD) including plasmaenhanced chemical vapor deposition (PECVD), low pressure chemical vapordeposition (LPCVD) and atomic layer chemical vapor deposition (ALCVD).In other embodiments, other suitable deposition techniques known in theart may also be used.

In one embodiment, the process can perform the sequence of actions in adifferent order. In another embodiment, the process can skip one or moreof the actions. In other embodiments, one or more of the actions areperformed simultaneously. In some embodiments, additional actions can beperformed.

In one aspect, the sensor fabrication methods of FIGS. 5a to 5k and/orFIG. 4 can be used to fabricate several different types of readers.These readers can include an antiparallel free layer (AP FL) type readhead, a two dimensional shape enhanced pinning (2D SEP) type read head,a reduced interlayer coupling (Hf) type read head, and/or a scissor rearsoft bias (SB) type read head. An example of an antiparallel free layer(AP FL) type read head may be found in U.S. Pat. No. 6,473,279 (e.g.,see FIG. 3A), the entire content of which is hereby incorporated byreference. In one aspect, antiparallel free layer (AP FL) type read headmay be characterized by an anti-parallel alignment between themagnetizations of the free layer (e.g., see 310 in FIG. 3A of U.S. Pat.No. 6,473,279) and an adjacent ferromagnetic layer (e.g., see 314 inFIG. 3A of U.S. Pat. No. 6,473,279). FIGS. 5a to 5k of the instantapplication show a two dimensional shape enhanced pinning (2D SEP) typeread head. In one aspect, the two dimensional shape enhanced pinning (2DSEP) type read head may be characterized by an extended pin layer shapedin more than one dimension.

An example of a scissor rear soft bias (SB) type read head may be foundin U.S. Pat. No. 9,099,122 (e.g., see FIGS. 4 and 5), the entire contentof which is hereby incorporated by reference. In one aspect, the scissorrear soft bias (SB) type read head may be characterized by a sensor thatuses only two magnetic free layers without additional pinning layers.The rear soft bias layer of U.S. Pat. No. 9,099,122 is shown as 402 inFIG. 4 and 804 in FIG. 9, and as being behind the sensor stack withreference to the ABS. On a side note, the soft bias of this disclosure(e.g., at 208 in FIG. 3) may be positioned at the rear of the sensorstack and/or on the sides of the sensor stack.

An example of a reduced interlayer coupling (Hf) type read head may befound in U.S. Pat. No. 9,099,122 (e.g., see FIGS. 4, 5, 28, 29). In oneaspect, the reduced interlayer coupling (Hf) type read head may becharacterized by a reduction in the Hf between scissor sensor freelayers (e.g., 304 and 306 in FIG. 3) brought about by an insulator layer(e.g., see 320 in FIG. 5 or insulator/dielectric 2502 in FIGS. 28/29) orinsulator structure (e.g., see 402 in FIG. 5 or bias/soft bias layer2504) positioned at the back edge of the sensor stack (e.g., see FIG. 5,28, or 29), where component and figure references used in this sentencerefer to U.S. Pat. No. 9,099,122.

FIG. 6 is a flowchart of a second process 500 for fabricating a magneticsensor with effectively shaped side shields in accordance with oneembodiment of the disclosure. In one aspect, the process 500 issubstantially similar to process 300 of FIG. 4 except that certainactions have been associated with the corresponding names of buildschemes (e.g., K3, K5, K1) or masks (KQ, L7). In one aspect, process 500may be used to fabricate the magnetic sensor 200 of FIG. 3, or any ofthe magnetic sensors with effectively shaped side shields disclosedherein.

In block 502, the process deposits sensor materials on a substrate.

In block 504, the process shapes the sensor materials to form a stripeheight of the magnetic sensor. In one aspect, the deposition and shapingof the sensor materials to form a stripe height may be referred to as aK3 build scheme (e.g., corresponding to the actions of blocks 402 to408), and may involve use of a K3 mask, which may be formed of resist(e.g., resist 456) and/or DLC (e.g., DLC 454 and DLC 454-2).

In block 506, the process shapes the sensor materials to form a trackwidth of the magnetic sensor. In one aspect, the shaping of the sensormaterials to form the track width may be referred to as a K5 buildscheme (e.g., corresponding to the actions of blocks 410 and 412), andmay involve use of a K5 mask, which may be formed of resist and/or DLC(e.g., DLC 460).

In block 508, the process deposits side shield materials (e.g.,corresponding to the action of block 414) on the shaped sensormaterials. In one aspect, the process deposits the side shield materialsafter depositing and patterning (e.g., etching using reactive ionetching or other suitable etching technique) a second photoresist layer.In one aspect, the process further deposits a fourth DLC mask layer onthe side shield materials. In one aspect, the second photoresist layerand/or fourth DLC mask defines a resulting height the side shield willhave. In one aspect, the second photo resist layer and/or fourth DLCmask may be referred to as a KQ mask.

In block 510, the process shapes the side shield materials (e.g.,corresponding to the action of block 416) such that a resulting sideshield extends further than the stripe height. In one aspect, theshaping may include removing the second resist layer and portions of thefourth DLC mask (e.g., those portions on the second resist layer).

In block 512, the process deposits an insulator layer (e.g.,corresponding to the action of block 418) on the shaped side shieldmaterials. In one aspect, the process deposits the insulator layer afterdepositing and patterning (e.g., etching using reactive ion etching orother suitable etching technique) a third photoresist layer, which maybe referred to as a L7 layer/mask.

In block 514, the process shapes the insulator layer. In one aspect, theshaping may include removing the third photoresist layer (L7 mask) andplanarizing the workpiece.

In block 516, the process deposits and shapes a pinned layer (e.g.,corresponding to the action of block 422). In one aspect, the depositingmay include depositing a fourth resist, and the shaping may includemilling portions of the side shield layer, the insulator layer, and/or apinned layer of the sensor stack. In one aspect, the shaping of thepinned layer may be referred to as a K1 build scheme (e.g., action ofblock 422), and may involve use of a K1 mask, which may be formed ofresist.

FIG. 7 is a top schematic view of various masking layers 600 that may beused in a process for fabricating a magnetic sensor with effectivelyshaped side shields in accordance with one embodiment of the disclosure.In one aspect, the various masking layers reflect the masking layersused in the fabrication processes of FIGS. 5a to 5k and FIG. 6 to form amagnetic sensor. The various masking layers 600 include a K3 maskinglayer 602, a K5 masking layer 604, a KQ masking layer 606, an L7 maskinglayer 608, and a K1 masking layer 610. In one aspect, the top view ofthe masking layers shown in FIG. 7 can be seen as illustrating therelative positioning and size of each of the masks.

The K3 masking layer 602 may be used to define a stripe height of themagnetic sensor. The K5 masking layer 604 may be used to define a trackwidth of the magnetic sensor. The KQ masking layer 606 may be used todefine a shape of the side shields of the magnetic sensor. The L7masking layer 608 may be used to define a shape of an insulation layerof the magnetic sensor. The K1 masking layer 610 may be used to define ashape of a pinned layer of the magnetic sensor, and possibly to furtherdefine a shape of the side shields of the magnetic sensor.

FIG. 7 also shows an approximate positioning of the ABS and thedistances between masks and the length of the K5 mask 604. Thesedistances and dimensions are merely exemplary and may be varied in otherembodiments.

FIG. 8 is a top schematic view of various masking layers 700 on amagnetic sensor workpiece that illustrate various constraints that maybe used in a process for fabricating a magnetic sensor with effectivelyshaped side shields in accordance with one embodiment of the disclosure.The various masking layers 700 include a KQ masking layer 706, an L7masking layer 708, and a KD mask 704. The KD mask 704 may be viewed as asubcomponent of the K5 mask (e.g., see mask 460 in FIGS. 5e and 5f ). Inone aspect, the top view of the masking layers shown in FIG. 8 can beseen as illustrating the relative positioning and size of each of themasks.

As to the constraints, FIG. 8 shows that the margin for the L7 mask 708to the KD mask 704 is about 50 nanometers (nm). Also, the KD mask 704 toKQ mask 706 is about 50 nm. In FIG. 7, the relative distance or marginfrom the KQ mask 606 to the K3 mask 602 can be between about 10 nm toabout 40 nm. In one aspect, maintaining this margin can enable higherrecording test amplitude and a minimal impact on servo head instability.In one aspect, any of these margins can have other suitable values suchthat the constraints are different.

In one aspect, and in addition to the constraints described above, thelength measurement for KQ-L7 can be a parameter of interest. In oneaspect, this parameter can be used for the sensor fabrication process toensure that K5's pocket is filled by either insulation or side shieldmaterials. If this parameter (KQ-L7) is smaller, CMP liftoff will beeasier (e.g., provide better results/performance). If this parameter(KQ-L7) is larger, L7's insulation may be on top of KQ's side shield andthe overall process might need longer CMP time for removal (e.g., CMP isless efficient).

In one aspect, and in addition to the constraints described above, thelength measurement for KQ-K3 can be a parameter of interest. In oneaspect, this parameter can be used for a sensor fabrication process toensure KQ's side shield covers K3's back edge for stability but if theparameter (KQ-K3) gets too large, the design may start to lose thedesired side shield shape anisotropy.

While the above description contains many specific embodiments of theinvention, these should not be construed as limitations on the scope ofthe invention, but rather as examples of specific embodiments thereof.Accordingly, the scope of the invention should be determined not by theembodiments illustrated, but by the appended claims and theirequivalents.

The various features and processes described above may be usedindependently of one another, or may be combined in various ways. Allpossible combinations and sub-combinations are intended to fall withinthe scope of this disclosure. In addition, certain method, event, stateor process blocks may be omitted in some implementations. The methodsand processes described herein are also not limited to any particularsequence, and the blocks or states relating thereto can be performed inother sequences that are appropriate. For example, described tasks orevents may be performed in an order other than that specificallydisclosed, or multiple may be combined in a single block or state. Theexample tasks or events may be performed in serial, in parallel, or insome other suitable manner Tasks or events may be added to or removedfrom the disclosed example embodiments. The example systems andcomponents described herein may be configured differently thandescribed. For example, elements may be added to, removed from, orrearranged compared to the disclosed example embodiments.

What is claimed is:
 1. A method of fabricating a magnetic sensor havingan air bearing surface (ABS), comprising: depositing sensor materials ona substrate; shaping the sensor materials to form a stripe height of themagnetic sensor; shaping the sensor materials to form a track width ofthe magnetic sensor; depositing side shield materials on the shapedsensor materials; shaping the side shield materials such that aresulting side shield extends further than the stripe height; depositingan insulator layer on the shaped side shield materials; and shaping theinsulator layer.
 2. The method of claim 1, wherein the depositing andshaping of the side shield materials is performed after the shaping thesensor materials to form the track width.
 3. The method of claim 1,wherein the depositing and shaping of the side shield materialscomprises: depositing and patterning a resist; depositing the sideshield materials on the shaped sensor materials and on the resist;depositing a mask on the side shield materials; and removing the resist.4. The method of claim 3, wherein the removing the resist comprisesremoving the resist and portions of the side shield materials and of themask previously deposited on the resist.
 5. The method of claim 1,wherein the shaping the insulator layer comprises shaping the insulatorlayer and further shaping the side shield materials.
 6. The method ofclaim 1: wherein the depositing sensor materials on the substratecomprises depositing a pinned layer on the substrate; and wherein theshaping the insulator layer comprises shaping the insulator layer andshaping the pinned layer.
 7. The method of claim 1, wherein the shapingthe insulator layer comprises shaping the insulator layer such that theshaped side shield materials are disposed between the shaped insulatorlayer and the ABS.
 8. The method of claim 1, wherein the depositing andshaping of the insulator layer comprises: depositing and patterning aresist; depositing an insulator layer on the shaped side shieldmaterials; and removing the resist such that such that the shaped sideshield materials are disposed between the shaped insulator layer and theABS.
 9. The method of claim 1, wherein the sensor materials comprise:materials for a pinned layer; materials for a barrier layer; andmaterials for a free layer.
 10. The method of claim 1, wherein theinsulator layer comprises TaOx, where x is a positive integer.
 11. Themethod of claim 1, wherein the side shield comprises one or morematerials selected from the group consisting of NiFe19, NiFe4,NiFe19/NiFe4, NiFe4/NiFe19, NiFe17Mo5, NiFe55, NiFe19/NiFeMo,NiFeMo/NiFe19, CoFe25, and combinations thereof.
 12. The method of claim1, wherein the magnetic sensor is a sub-component of a reader selectedfrom the group consisting of an antiparallel free layer (AP FL) typereader, a two dimensional shape enhanced pinning (2D SEP) type reader, areduced interlayer coupling (Hf) type reader, and a scissor rear softbias (SB) type reader.
 13. The method of claim 1, wherein the depositingthe sensor materials on a substrate comprises: depositing materials fora pinned layer on the substrate; depositing materials for a barrierlayer on the pinned layer; and depositing materials for a free layer onthe barrier layer, wherein the stripe height of the magnetic sensor isdefined by a stripe height of the free layer.
 14. The method of claim13, wherein a stripe height of the pinned layer is greater than thestripe height of the free layer.